Platelet granule exocytosis and thrombus formation

血小板颗粒胞吐作用和血栓形成

基本信息

批准号：
8436082
负责人：
Robert C Flaumenhaft
金额：
$ 43.5万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-02-01 至 2017-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8436082
关键词：
Actins Address Adhesions Alpha Granule Blood Platelets Cells Coagulation Process Cytoplasmic Granules Cytoskeleton Disease Dynamin Dynamin 2 Dynamin III Evaluation Event Exocytosis Foundations Genetic Screening Hemostatic function Heterogeneity In Vitro Individual Inflammation Kinetics Laboratories Learning Malignant Neoplasms Mediating Membrane Membrane Fusion Molecular Molecular Chaperones Monitor Morbidity - disease rate Movement Mus Myocardial Infarction Platelet Activation Population Protein Isoforms Proteins Regulation Role SNAP receptor Sorting - Cell Movement Speed Stroke Structure Suspension substance Suspensions Thrombosis Thrombus Vascular Diseases Video Microscopy Wound Healing angiogenesis cellubrevin chaperone machinery chemical genetics controlled release in vivo intravital microscopy mortality neglect novel protein function public health relevance research study segregation trafficking vesicle-associated membrane protein

项目摘要

DESCRIPTION (provided by applicant): Granule exocytosis is an essential platelet function, contributing not only to hemostasis and thrombosis, but also to inflammation, wound healing, malignancy, and angiogenesis. Previous efforts to understand the molecular mechanisms of granule exocytosis have identified the SNARE machinery and chaperone proteins required for membrane fusion. Studies described in this proposal will evaluate the premise that this machinery serves a role in sorting specific cargos to distinct subpopulations of ¿-granules and enabling differential release of granule contents upon platelet activation. We will study granule segregation and secretion in mice lacking VAMP-3, VAMP-5, VAMP-7, and VAMP-8. Cytoskeleton dynamics that occur during platelet spreading can influence SNARE interactions and modify granule exocytosis. We will evaluate granule exocytosis during platelet spreading. These studies will also assess the role of exocytosis in providing membrane for growing actin structures at the periphery of adherent platelets and for directed spreading and movement on micropatterned matrices of adhesion proteins. Use of high-speed intravital microscopy will be used to monitor release of granules from individual platelets during thrombus formation in vivo. These approaches will allow us to evaluate the hypothesis that the mechanism of granule secretion is altered in adherent platelets compared to suspension platelets. We will also evaluate the role of dynamins in controlling fusion pore dynamics, demonstrating a level of control of platelet exocytosis that occurs following SNARE-mediated membrane fusion. These studies will use single-cell amperometry to monitor the release of individual granules from single platelets. The role of dynamins in controlling platelet exocytosis during thrombus formation in vivo will evaluate the hypothesis that the platelet fusion pore can be regulated to control thrombus formation. These experiments will address poorly understood aspects of platelet granule exocytosis and provide a foundation for targeting select platelet membrane fusion events during thrombosis.

描述（由申请人提供）：颗粒胞吐作用是一种重要的血小板功能，不仅有助于止血和血栓形成，而且还有助于炎症、伤口愈合、恶性肿瘤和血管生成，之前为了解颗粒胞吐作用的分子机制所做的努力已经确定了 SNARE。该提案中描述的研究将评估该机器在将特定货物分类到不同亚群中的作用的前提。 ¿ -颗粒并在血小板激活时实现颗粒内容物的差异释放我们将研究缺乏 VAMP-3、VAMP-5、VAMP-7 和 VAMP-8 的小鼠中颗粒的分离和分泌，血小板扩散过程中发生的细胞骨架动力学会影响 SNARE。我们将评估血小板扩散过程中的颗粒胞吐作用，这些研究还将评估胞吐作用在为生长肌动蛋白结构提供膜方面的作用。粘附血小板的外围以及粘附蛋白微图案基质上的定向扩散和运动将用于监测体内血栓形成过程中单个血小板的颗粒释放。与悬浮血小板相比，粘附血小板的颗粒分泌机制发生了改变。我们还将评估动力在控制融合孔动力学中的作用，证明控制水平。这些研究将使用单细胞电流分析法来监测单个血小板中单个颗粒的释放，动态蛋白在体内血栓形成过程中控制血小板胞吐作用的作用将评估以下假设：可以调节血小板融合孔来控制血栓形成，这些实验将解决人们对血小板颗粒胞吐作用知之甚少的问题，并为靶向选择性血小板膜融合提供基础。血栓形成期间的事件。